1. Field of the Invention
The invention relates to a structure design for projector screen. Especially it refers to a projector screen structure that is suitable for various types of projectors which have different project screen requirements.
2. Description of the Prior Art
The pursuit for home theater effect has driven the projector screen from the early simple white wall type for single-function projector to advance projector screen for multi-function projector. The latter type of projector screen is usually divided into woven or elastic screen based on the material used. Generally, woven screens have rough texture which reduces image clarity and generates Moire pattern when projected on. The elastic screens are generally made from plastics and PVC and the screen surface is pressed to produce irregular pattern to allow better diffusing of light, as well as increasing view angle and picture uniformity. Since the projectors are developed to be multi-functional, the screens can be further divided into reflective type and transmitive type. The reflective type is used for front projection, while the transmitive type is used for rear projection.
In practice, a user would select a suitable projector and project screen that best fit his/her viewing objective. For example, if the objective is for small number of audience in a confined space, a metallic screen with small viewing angle and high light concentration may be selected; and whereas, for a large number of audience in a more opened space, a plastic screen with wide viewing angle and low light concentration may be selected.
Every type of screen has its own advantages and disadvantages and may not be suitable for all projectors. For example, although the white plastic screen has wide viewing angle, it's relatively dimmer and has low light reflective characteristic which would blur projected image and reduce picture quality. In a glass bead screen the surface is treated with an optical coating layer to increase image brightness and reflection, however, reflection may become too bright that is glaring to the eyes. Besides, the coating layer may not have good uniformity, which results in uneven reflection. Other problem concerning the conventional projector screen is that the chemical spray use in the manufacturing process can cause air pollution and secondary environmental issues when is disposed. Other screens may have disadvantages in limitation to single-side use, radiation effect, lacking water cleanability, uneven light absorbance and reflection, more weight for the same size screen. All these indicate there is a need of further improvement for the traditional screens.
The inventor actively sought solutions to benefit the general users by analyzing the drawbacks for all projectors screens, experimenting, making improvements, and finally developed a new type of screen with improved structure that is suitable for any type of projectors.